1918] FITZPATRICK—RHIZINA 221 
11. With the outward flow of nuclei and cytoplasm into the 
ascogenous hyphae, the cytoplasm in the ascogonial cells of the 
archicarp becomes pronouncedly vacuolated. The nuclei are then 
seen to lie in pairs. In preceding stages the dense nature of the 
protoplasm and the crowding of the nuclei render the demonstration 
of a paired condition extremely difficult. Pairs of nuclei in the 
archicarp have been seen only in cells giving rise to ascogenous 
hyphae. 
12. Careful search has failed to demonstrate stages of nuclear 
fusion in the ascogonial cells or in the ascogenous. hyphae. 
13. Paired nuclei are also present in the ascogenous hyphae. 
Neither conjugate nor simple divisions have been demonstrated. 
14. Crozier formation takes place, but elaborate systems of 
hooks at the ends of the ascogenous hyphae have not been found. 
Nuclear fusion occurs in the young ascus. 
DEPARTMENT OF PLANT PATHOLOGY 
CORNELL UNIVERSITY 
LITERATURE CITED 
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, The origin and development of the apothecium in Collema pul- 
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Bavr, E., Zur Frage nach — Sexualitat der Collemaceen. Ber. Deutsch. 
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